新冠疫情背景下城市创新生态系统韧性测算指标体系设计

随着创新资源越来越向（大）城市集中,城市创新生态系统的形成过程成为一个实现城市高端化发展的过程,城市创新生态系统韧性的提升有助于提高城市创新生态系统对抗外部冲击和干扰的抵御能力以及恢复能力。新冠疫情发生以来,其对各个城市的创新活动造成了一定影响,各城市在抵御外部冲击并恢复状态的能力需要进行有效测算。通过对相关研究成果的梳理发现,关于城市韧性和创新生态系统的研究成果丰富,但关于城市创新生态系统韧性的研究较少,并鲜有融入新冠疫情特点的城市创新生态系统韧性的评价研究。基于此,以城市创新生态系统韧性为研究对象,融入新冠疫情特点,构建一套适用于疫情背景下的城市创新生态系统韧性测算指标体系,以此获得各城市的创新生态系统韧性水平。     

对后疫情时代园林设计的再思考

分析园林设计的主要议题、公共健康与园林景观设计的关系、历史上重大公共卫生事件对风景园林景观设计的影响,反思园林景观设计的不足。从生态、人居、韧性城市的角度出发,提出构建自然与生物协调的生态系统,构建人居多功能绿地环境,满足韧性城市防灾害的发展需求,以及建设通风廊道等建议。     

韧性乡村对乡村建设的意义探究

指出了目前蓬勃发展的乡村建设取得了一系列成果,也存在一些破坏原有乡村生态体系的问题,种种现象表明提升乡村建设的先导性、可持续发展思路不够明确。从韧性城市中得到启发,将韧性理论引入乡村建设中,提出了韧性乡村的概念以及内容框架,并从生态韧性、经济韧性、文化韧性、社会韧性4个维度出发,讨论了韧性乡村发展的重要意义,希望为乡村振兴的可持续发展提供新的视角和思路。     

巴塞罗那城市公园发展更新与特征研究

巴塞罗那城市规划与空间更新作为世界典范,其城市公园更新与发展历程也值得学习与借鉴.结合对巴塞罗那城市更新计划与政策背景的分析,梳理与分析了巴塞罗那城市公园发展的历史进程,将其分为3个主要阶段:注重将自然引入城市的萌芽期(19世纪50年代—20世纪70年代);寻求人与自然和谐的发展期(20世纪80—90年代);思考人、自...     

环渤海地区海洋经济韧性评价

从“抵抗恢复-适应调整-创新转型”的研究框架构建海洋经济韧性评价指标体系,运用熵值-TOPSIS法对环渤海17个沿海地级市的海洋经济韧性进行了测度,对其时空特征进行了分析,并进一步测度了影响海洋经济韧性水平的主要障碍因素。结果表明：环渤海地区海洋经济韧性呈缓慢上升态势,整体呈向高水平迈进的趋势,各城市间相对差异有所扩大;对环渤海海洋经济韧性水平起主要作用的是适应调整能力,创新转型能力发展潜力较大;环渤海海洋经济韧性影响较大的是就业情况和沿海基础设施建设情况。因此,从改善城市经济环境、完善基础设施建设、加大科研扶持力度、人才吸引与培养4个方面入手,提出了相应的政策建议,以期为海洋经济韧性发展提供依据。     

城市森林的兴起及其发展趋势

科学家根据3000多年城市园林发展的历史经验和今后城市居民的生活、生存需要, 提出在城市内发展城市森林, 以创造无污染或少污染、优美舒适的生活环境, 解决城市居民部分能源和资源短缺问题, 本文从城市森林的兴起背景、城市森林的概念、范围、发展简史、效益和今后的发展趋势等较全面地概述了国外城市森林的发展, 也谈到了我国城市森林的发展情况。     

城市科学绿化助力生态平衡

在城市特殊环境中,人类高密度聚集,生产生活高度集中的各种行为,导致自然界失衡,怎样通过城市科学绿化把有限城市空间作为有机整体,统筹规划,合理种植,激发植物生命潜能,发挥植物“碳中和”和“生物多样性”功能,建设“无废城市”,“韧性城市”,恢复低碳循环生机,助力城市生态平衡,是园林工作者值得思考的问题。     

常态化风险防控下旅游古村落组织韧性提升机制研究

在全域旅游、乡村旅游不断发展的背景下,古村落的旅游价值正不断得到重视,旅游业对稳定乡村人力资源、助力乡村发展的作用越发凸显,在常态化风险防控和全面推动乡村振兴情境下,韧性成为旅游古村落风险治理与可持续发展的新思路.以广东丹霞山夏富古村为例,通过定性和定量相结合的方法,挖掘了影响旅游古村落组织韧性的重要因素,并构建模型进...     

城市湖泊治理模式创新问题研究——以武汉市为例

从总结武汉市的湖泊治理经验入手,分析治理工作与治理模式存在的问题,提出了思维模式、管理模式、技术模式和发展模式等多样化的城市湖泊治理模式创新设想,并从城市与湖泊的历史演变、空间发展关系、污染治理的技术路径理想化、湖泊污染复杂性、城市湖泊生命周期以及城市发展必然性等方面进行了初步分析,给城市湖泊治理工作提供了一个比较新的、全面的思路.     

中山市建设花园式城市的现实与展望

花园式城市是以丰富的植物资源,充裕的园林绿地、科学的空间布局、优美的园林景观与完善的园林设施为条件,以发挥植物的生态功能,美化城市环境,增进市民身心健康的效益。在改革开放深入发展的今天,城市园林化、改善必然会为吸引建设资金,发展旅游、兴办第二产业、促进经济发展方面创造条件;对两个文明建设、加强城市综合实力、扩大城市影响、提高城市地位方面都有密切关系。实际上,花园式城市建设,关系到每个市民、渗透各行各业,覆盖全社会,是一项列入国民经济计划和社会发展计划的系统工程,其兴衰成败,关键还在于政府的决策保证、远见卓识的规划指导、有可供开发利用的自然资源和经济投入以及全市人民的参与,否则,是无从实现的。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.